Rome: The leaders of the euro zone's four biggest economies on Saturday vowed measures worth up to 130 billion euros (USD 163 billion) to tackle the bloc's relentless debt crisis.

Meeting for talks in Rome ahead of a crucial EU summit in Brussels next week, the leaders of Germany, France, Italy and Spain looked to soothe global worries with promises to kick start growth in the bloc's floundering economies.

French President Francois Hollande said the leaders had agreed to mobilise "one percent of European GDP, that is 120 to 130 billion euros, to support growth" -- a move Germany's Angela Merkel hailed as "an important signal".

Italian Prime Minister Mario Monti said the four leaders had agreed that boosting growth in the euro zone was key to restoring confidence.

"The first objective we agree on is to relaunch growth, investments and to create jobs," Monti said at a press conference after the talks.

"The euro is here to stay and we all mean it," he added. "The great project which has been successful until now, the euro, is irreversible."

Hollande last week proposed a 120 billion euro "growth pact" to tackle the debt crisis, though much of the money comes from already existing programmes.

The measures would include a capital injection for the European Investment Bank, the redirection of some unspent EU regional funds and "project bonds" to finance infrastructure works.

But Merkel, who has led the drive for euro zone austerity, said more moves for financial and political integration were necessary to overcome the debt crisis in the long term.